fix error message for non logged in

app.py

@@ -58,7 +58,7 @@ def split_upload_model(model_path: str, outdir: str, repo_id: str, oauth_token:
     print(f"Model path: {model_path}")
     print(f"Output dir: {outdir}")
 
-    if oauth_token.token is None:
+    if oauth_token is None or oauth_token.token is None:
         raise ValueError("You have to be logged in.")
     
     split_cmd = [